Half to robert t



(No Model.) O. M. ALLEN.

ELECTROMAGNETIC TRAGTILB DEVICE.

No. 525,523. Patented Sept. 4, 1894.

UNITED STATES PATENT OFFICE.

CHARLES M. ALLEN, OF SAN FRANCISCO, CALIFORNIA, ASSIGNOR OF ONE- HALF TOROBERT T. MURRAY, OF SAME PLACE.

ELECTROMAGNETIC TRACTILE DEVICE.

SPECIFICATION forming part of Letters Patent No. 525,523, datedSeptember 4, 1894.

Application filed August 22, 1893- Serial No.483, 761. (No model) To allwhom it may concern:

Be it known that I, CHARLES M. ALLEN, a citizen of the United States,residing in the city and county of San Francisco, State of California,have invented an Improvement in Electromagnetic Tractile Devices; and Ihereby declare thefollowing to bea full, clear, and exact description ofthe same.

My invention relates to a novel device for increasing the tractile powerof electrical and other motor engines, or locomotives, and it consistsof the constructions and combinations of devices which I shallhereinafter fully describe and claim.

Figure l is a view illustrating the application of my device. Fig. 2 isa plan view of the same. Fig. 3 is a modification. Fig. 4 is a plan Viewof it.

The object of my invention is to provide a means for temporarilyincreasing the tractile force of the wheels of a vehicle, so that theywill be prevented from slipping when power is applied to start the motoror train, or to climb steep grades, or under any condition in which itis desirable to increase the tractile power. This result is obtained bythe use of powerful electro magnets so arranged with relation to therails of the track over which the car passes that when the magnets areenergized the structure upon which they are mounted will be attractedtoward the rails with a powertdependent upon the magnetic strengthdeveloped, and this attraction is equivalent to the addition of agreater weight to the vehicle whereby the adhesion of the wheels to therails is correspondingly increased.

The magnets A may be arranged in any suitable or desired manner andsupported from some part which maintains a fixed dis-- tance from thetrack. In the present case I have shown them as supported from the caror truck frames or axles, and movable vertically. These magnets areformed in the usual or any suitable manner, by surrounding them withcoils of insulated conducting wire, said coils being wound eitherdirectly or in independent series, and provided with means for passingthe current through as many of the series as necessary to develop therequired magnetic power. These magnets are mounted either between thewheels of the trucks in line above the rails, or in any suitablerelation thereto for the development of the desired power, and tomaintain them in a fixed relation to the track. They are also madevertically movable so that they may be approached close to the rails orwithdrawn therefrom as may be desired.

Fig. 1 shows the magnets mounted upon a frame which is so constructed asto move in vertical guides C, and they may be raised or depressed eitherby toggle levers, by cams or eccentrics, or by inclined planes, as shownin Fig. 1, or screws, as shown in Fig. 2, or any other mechanical devicewhich will produce the desired result. In Fig. 1, I have shown themagnet frame as having projecting lugs D upon each side which travelupon inclined planes F. These inclined planes are fixed to a plate Fwhich slides upon a guide plate I. The plate'F' is slotted and pins Jextend up through these slots from the plate I and thus limit themovement of the inclined planes, which move beneath the lugs D, and areconnected by a rod G with a lever E or other mechanism within convenientreach of the operator whereby he may move the inclines so as to raisethe magnets a considerable distance above the track. When released, theinclined planes are drawn back by action of a spring H. When constructedas shown in Fig. 3, the curved planes F are rotated a part of arevolution by levers or by chainsLpassing around them as shown, themovement acting upon the pins D to raise the magnets in the same manneras described for the straight inclines. Theinclined planes travel upon asupporting horizontal guide-plate I, and act as before described toelevate or depress the magnets through the projecting lugs, and atwhatever point the magnets are arrested with relation to the track, theywill,

whenever a current of electricity is passed through the coilssurrounding them, be attracted with a corresponding force, and this willadd to the weight upon the wheels in proportion to the magnetic forcedeveloped.

When the motor car or locomotive is to be started upon a level track,and it is desired to increase its tractile force, the magnets will belowered to a point very near to the surface of the track, and theelectrical current being passed through the coils, will develop a strongattractive force in the magnet which will be equivalent to the additionof that much weight, and thus increase the adhesion of the wheels to therails. The same operation is employed when the motor is climbing gradeswhere the adhesive force of the wheels must be increased, the magnetsmaybe raised from the rails either to decrease the force of attraction,or when passing over curved or rough places of the track where it isnecessary to raise them to prevent contact.

Having thus described my invention, what I claim as new, and desire tosecure by Letters Patent, is-

1. A means for increasing the traetile force of motors consisting of anelectro-magnet or magnets Vertically movable toward and from CHARLES M.ALLEN.

Witnesses:

S. H. NoURsE, H. F. ASOHECK.

